Electric utility meters, or simply meters, are devices, that among other things, measure electrical energy consumed by a residence, factory, commercial establishment or other such facility. Electrical utilities rely on meters for many purposes, including billing customers and tracking demand for electrical power. A common form of meter utilizes current transformers to sense the electrical current being supplied to the facility being metered. The current sensed by the current transformers is transmitted to circuit boards included in the meter to facilitate measurement of the amount of electrical energy being consumed by the facility.
Heretofore, current transformers have been positioned inside of and secured to meter housings in a variety of ways. For example, one way of securing a current transformer to a meter housing involves attaching a post to a meter base plate within the housing and then inserting the post through a hole defined in the center of the current transformer. The current transformer is then retained on the post by pressing a nut over the end of the post. Alternatively, the end of the post may be melted such that the melted end bonds with the current transformer thereby retaining the current transformer on the post.
Although the above described methods for securing a current transformer to a meter are commonly used, they do have significant disadvantages. For example, melting the end of the post, or having to push a nut over the end thereof, requires manufacturing steps that increase the complexity of manufacturing the meter. In addition, the use of such methods to secure the current transformers within the meter housing inhibits the ability to service the meter. In particular, if a current transformer must be replaced in the meter, then a service technician can encounter difficulty in removing the existing current transformer and inserting a new current transformer. Specifically, if the melting method was utilized for securing the current transformer, the melted end of the post must be cut off before the current transformer can be removed from the post within the meter housing. Once the post end is cut off, it cannot be easily reused, and often the entire meter base plate must be replaced. If, however, a nut was used to secure the current transformer, then the nut must be carefully removed from the post to avoid damaging the current transformer. Carefully removing the nut to avoid damaging the current transformer results in a technician spending additional time disassembling the meter which also increases the cost of servicing the meter.
There exists a need, therefore, for a method and arrangement for securing a current transformer to an electric utility meter housing which addresses one or more of the above discussed problems.